src/gpu/GrClipStackClip.h

/*
 * Copyright 2016 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */
#ifndef GrClipStackClip_DEFINED
#define GrClipStackClip_DEFINED

#include "src/core/SkClipStack.h"
#include "src/gpu/GrClip.h"
#include "src/gpu/GrReducedClip.h"

class GrPathRenderer;
class GrTextureProxy;

/**
 * GrClipStackClip can apply a generic SkClipStack to the draw state. It may need to generate an
 * 8-bit alpha clip mask and/or modify the stencil buffer during apply().
 */
class GrClipStackClip final : public GrClip {
public:
    GrClipStackClip(const SkClipStack* stack = nullptr,
                    const SkMatrixProvider* matrixProvider = nullptr) {
        this->reset(stack, matrixProvider);
    }

    void reset(const SkClipStack* stack, const SkMatrixProvider* matrixProvider) {
        fStack = stack;
        fMatrixProvider = matrixProvider;
    }

    bool quickContains(const SkRect&) const final;
    bool quickContains(const SkRRect&) const final;
    SkIRect getConservativeBounds(int width, int height) const final;
    bool apply(GrRecordingContext*, GrRenderTargetContext*, bool useHWAA,
               bool hasUserStencilSettings, GrAppliedClip* out, SkRect* bounds) const final;

    bool isRRect(const SkRect& rtBounds, SkRRect* rr, GrAA* aa) const override;

    sk_sp<GrTextureProxy> testingOnly_createClipMask(GrContext*) const;
    static const char kMaskTestTag[];

private:
    static bool PathNeedsSWRenderer(GrRecordingContext* context,
                                    const SkIRect& scissorRect,
                                    bool hasUserStencilSettings,
                                    const GrRenderTargetContext*,
                                    const SkMatrix& viewMatrix,
                                    const SkClipStack::Element* element,
                                    GrPathRenderer** prOut,
                                    bool needsStencil);

    bool applyClipMask(GrRecordingContext*, GrRenderTargetContext*, const GrReducedClip&,
                       bool hasUserStencilSettings, GrAppliedClip*) const;

    // Creates an alpha mask of the clip. The mask is a rasterization of elements through the
    // rect specified by clipSpaceIBounds.
    GrSurfaceProxyView createAlphaClipMask(GrRecordingContext*, const GrReducedClip&) const;

    // Similar to createAlphaClipMask but it rasterizes in SW and uploads to the result texture.
    GrSurfaceProxyView createSoftwareClipMask(GrRecordingContext*, const GrReducedClip&,
                                              GrRenderTargetContext*) const;

    static bool UseSWOnlyPath(GrRecordingContext*,
                              bool hasUserStencilSettings,
                              const GrRenderTargetContext*,
                              const GrReducedClip&);

    const SkClipStack*      fStack;
    const SkMatrixProvider* fMatrixProvider; // for applying clip shaders
};

#endif // GrClipStackClip_DEFINED